EMPLOYEE RETIREMENT PLANS - Information Relating to the Company's Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Change in benefit obligation:
Benefit obligation, beginning of year	$ 51,117	$ 44,055
Service cost	1,092	969
Interest cost	1,285	1,613
Actuarial loss	25,033	4,480
Benefit obligation, end of year	78,527	51,117
Unfunded status of the plan, end of year	78,527	51,117
Noncurrent liability	$ 78,527	$ 51,117